This invention relates to an automatic drip or ADC coffee maker.
A common form of ADC coffee maker includes a housing for a cold water compartment, a warmer plate, an ADC heater and pump assembly, and a brew basket or the like. Cold water in the cold water compartment is heated and pumped through an up tube or riser to a spreader tube and poured into the brew basket where it engages coffee grounds previously placed in the basket, forms brewed coffee, and drains into a separate coffee container or carafe that is removably positioned on the warmer plate. Coffee brewed in this manner is generally preferred to percolator brewed coffee, apparently because the freshly heated hot water passes only once through the coffee grounds whereas, in a percolator, partly brewed coffee recycles through the coffee grounds.
An object of this invention is to provide an ADC coffee maker which does not have a separate carafe. Rather, the coffee maker is a single unit in the sense that all of its parts, including the carafe, are in one housing so that it may be carried about and stored in the same manner as an ordinary percolator. Various suggestions and attempts have been made to provide such an ADC coffee maker. However, the known coffee makers of this type have been designed so that they would be excessively large in relation to the amount of coffee that may be brewed at any one time, either in a vertical or in a horizontal direction, or quite expensive, or quite complex and unreliable.
A further object of this invention is to provide such a single-unit ADC coffee maker which is relatively inexpensive, attractively styled, convenient and safe to use, and easy to clean.
Another object of this invention is to provide such a single-unit ADC coffee maker having a housing molded from a thermoplastic material having compartments for containing both the cold water and the brewed coffee, wherein a single ADC heater and pump assembly is used to heat the cold water for brewing and for maintaining the brewed coffee warm after brewing. A related object is to provide such a coffee maker in which the thermoplastic material in the area of the ADC heater and pump assembly is not heated to the extent that it may soften and lose its shape. Also, it is an object to provide such a coffee maker wherein the brewed coffee compartment is in a container comprising a thermoplastic, cylindrical member open at its upper end and closed at its lower end by a metal warmer plate. Although several thermoplastic materials may be used, polypropylene is presently considered to be the material of choice. An ADC heater and pump assembly is preferably mounted on the bottom of the warmer plate and the warmer plate preferably comprises a stainless steel plate seamed in liquid tight relationship to the bottom of the cylindrical, thermoplastic body member.
Another object of this invention is to provide an ADC coffee maker having a brewed coffee container located within a cold water compartment wherein the brewed coffee stays warm over relatively long periods of time if its heater is disconnected from a source of electricity and wherein the outside of the coffee maker housing remains relatively cool so that it may be safely and comfortably handled. To this end, the brewed coffee container is surrounded partly by the cold water compartment and otherwise substantially surrounded by dead air space. During the brewing process, the cold water compartment is emptied so that the freshly brewed coffee is substantially completely surrounded by dead air spaces and thereby insulated from the outer wall of the coffee maker.
Briefly, an ADC coffee maker in accordance with this invention has a brewed coffee container located within a housing, the brewed coffee container having a pour spout at its upper end extending upwardly and outwardly to the outside of the coffee maker. The brewed coffee container is formed from a thin-walled, generally cylindrical plastic body member open at its upper end and closed at its lower end by a metal warmer plate, the outer margin of which is seamed to the bottom of the plastic body member. An ADC heater and pump assembly is mounted on the underside of the warmer plate. The coffee maker further includes a brew basket removably mounted in the upper end of the brewed coffee container. A removable lid is provided to permit access to the portion of the housing containing the brewed coffee container to permit access to the brew basket and the brewed coffee container.
A cold water compartment having a fill port adjacent the brew basket surrounds part of the brewed coffee container. The fill port is located within a cold water compartment cover panel that spans between the upper end of the brewed coffee container and a wall of a housing that houses the cold water compartment and the brewed coffee container. Removal of the lid also provides access to the cold water fill port.
A hot water spreader or spigot is provided for delivering water pumped through hot water delivery means from the ADC pump to the brew basket. The spigot is pivotal about a generally vertical axis so that it may be pivoted to a position wherein it does not interfere with the removal of the brew basket means.
The coffee maker housing is so constructed that, after the cold water has been pumped from the cold water compartment, the brewed coffee container is substantially completely surrounded by dead air spaces which insulate the brewed coffee container from the outer walls portions of the coffee maker. Means are provided for restricting heat losses through the spout and also to prevent substantial spillage of brewed coffee or coffee grounds if the coffee maker is accidentally upset.
In the presently preferred embodiment of this invention, the housing comprises a thermoplastic upper housing member and a thermoplastic lower housing member that are bonded together to form and enclose the cold water compartment and also to form all of the brewed coffee container except for the warmer plate which closes its lower end. A hollow handle may form part of the cold water compartment.
Still a further object of this invention is to provide an improved brew basket especially adapted for use with an ADC coffee maker. In accordance with this invention, the brew basket comprises a cup-like body for receiving a filter and fresh coffee grounds and having means at its upper end for deriving support from a brewed coffee container. The floor of the brew basket slopes downwardly from front to rear and a coffee drain port is at the rearward end of the floor. The floor has side edges converging from a maximum separation at its front end to a lesser separation at its rearward end. By proper selection of the slope of the floor and its width, the proper pressure head of brewed coffee is formed for the desired rate of flow of the brewed coffee through the drain port. The brew basket further comprises a baffle along the upper front margin thereof to protect against coffee grounds falling out of the basket when brewed coffee is being poured.
Other objects, advantages, and features of the invention will become apparent from the following description, the claims, and the accompanying drawings.